Outside plaster making hollow sound?
There is cracks and a hollow sound in 5 places on my newly plastered outside wall. What could the problem be?
11 Answers
Mr.Yanev
0 Reviews
old plaster or there was water and this water when it evaporated left air between the wall and the plaster. it just needs to be torn down as much as possible and inspected again and plastered
2nd Mar 2021
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Jpkempplasterers
0 Reviews
If crack and hollow sound like it blown
When had scratch coat applied did it allow 7 day in to cure before top coat ??
When had scratch coat applied did it allow 7 day in to cure before top coat ??
16th Jan 2021
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FB Contracts Ltd
1 Reviews, 100% Positive
Hi , this sounds like the render has de-bonded from the wall, allowing the air to get underneath. Which makes the hollow sound, i would have these areas re done to prevent them from completely falling down.
11th Jan 2021
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It sounds like your render has blown, the more the moisture gets into the cracks the worse it will get, especially if it rains then freezes
16th Dec 2020
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A&GO
0 Reviews
Sounds like he's chopped it back but not prepped the wall properly to control the suction. The wall has then sucked out the water from the undercoat plaster which is now not adhering to the wall.
Hope that helps
Hope that helps
1st Jan 2021
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Chislehurst property solutions
39 Reviews, 95% Positive
First off it should be render or k rend & not plaster outside... Also if it sounds Hollow, It sounds to me like it has blown, which needs to be hacked off and re-done.
8th Dec 2020
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Dpc construct ltd
1 Reviews, 100% Positive
Could be the cause of many things first I have to see to tell what it's all about (could be air pocket ,dust creating air pocket,could be an area with no good pva application I have to see etc..
3rd Jan 2021
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afy plastering services
0 Reviews
sonds like it has come away from the wall not bonded properly
2nd Feb 2021
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AA Trading
0 Reviews
The old walls may have been painted with an oil based paint which will repel the plaster
11th Feb 2021
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If the render is on brick/block then it shouldn’t have any hollow sounds when tapped… the cracks will allow the water to get in and eventually just gets more defected over time… I would call the plasterer back to give his take on it but if it’s cracked an hollow then it sounds like it will have to come off and be re-done unfortunately
8th Mar 2022
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Jace Orzechowski
0 Reviews
probably the work was done incorrectly, not enough materials were used previously
28th Apr 2023
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